diff --git a/go.mod b/go.mod
index 0ffbc6fd2..fd2bb0e13 100644
--- a/go.mod
+++ b/go.mod
@@ -8,7 +8,7 @@ require (
 	github.com/Workiva/go-datastructures v1.0.53
 	github.com/btcsuite/btcd v0.21.0-beta
 	github.com/btcsuite/btcutil v1.0.2
-	github.com/confio/ics23/go v0.6.3
+	github.com/confio/ics23/go v0.6.6
 	github.com/cosmos/iavl v0.15.3
 	github.com/fortytw2/leaktest v1.3.0
 	github.com/go-kit/kit v0.10.0
diff --git a/go.sum b/go.sum
index cc687c3fd..1792f6b11 100644
--- a/go.sum
+++ b/go.sum
@@ -83,8 +83,9 @@ github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnht
 github.com/cockroachdb/datadriven v0.0.0-20190809214429-80d97fb3cbaa/go.mod h1:zn76sxSg3SzpJ0PPJaLDCu+Bu0Lg3sKTORVIj19EIF8=
 github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd/go.mod h1:sE/e/2PUdi/liOCUjSTXgM1o87ZssimdTWN964YiIeI=
 github.com/confio/ics23/go v0.0.0-20200817220745-f173e6211efb/go.mod h1:E45NqnlpxGnpfTWL/xauN7MRwEE28T4Dd4uraToOaKg=
-github.com/confio/ics23/go v0.6.3 h1:PuGK2V1NJWZ8sSkNDq91jgT/cahFEW9RGp4Y5jxulf0=
 github.com/confio/ics23/go v0.6.3/go.mod h1:E45NqnlpxGnpfTWL/xauN7MRwEE28T4Dd4uraToOaKg=
+github.com/confio/ics23/go v0.6.6 h1:pkOy18YxxJ/r0XFDCnrl4Bjv6h4LkBSpLS6F38mrKL8=
+github.com/confio/ics23/go v0.6.6/go.mod h1:E45NqnlpxGnpfTWL/xauN7MRwEE28T4Dd4uraToOaKg=
 github.com/coreos/bbolt v1.3.2/go.mod h1:iRUV2dpdMOn7Bo10OQBFzIJO9kkE559Wcmn+qkEiiKk=
 github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
 github.com/coreos/etcd v3.3.13+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=